Fix bm_tornado_http on Python 3.9 and newer

Author: vstinner

pyperformance/benchmarks/bm_tornado_http.py

@@ -93,7 +93,7 @@ def run_client():
     # https://bugs.python.org/issue37373
     # https://github.com/python/pyperformance/issues/61
     # https://github.com/tornadoweb/tornado/pull/2686
-    if sys.platform == 'win32' and sys.version_info[:2] == (3, 8):
+    if sys.platform == 'win32' and sys.version_info[:2] >= (3, 8):
         import asyncio
         asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())